"I couldn't get over how poorly he looked when I saw him last month," Father Walshe said.

"He'd put on a lot of weight, he is not moving very well and I just thought his general demeanour was very grey."

Bishop 'profoundly sorry'

The former bishop of Ballarat, Ronald Mulkearns, has trouble sleeping at night because of his failure to stop paedophile priests preying on children in his diocese, the Royal Commission into Institutional Responses to Child Sexual Abuse has heard.

Father John McKinnon said Bishop Mulkearns was profoundly sorry for failing to protect children.

"He says he still struggles to sleep of a night," Father McKinnon said.

Father McKinnon said the retired bishop could not remember specific details about the time.

"He didn't remember details. But he was profoundly sorry for what he'd done," Father McKinnon said.

Bishop Mulkearns will not appear at the child abuse royal commission due to ill health.

The hearing was told Bishop Mulkearns received numerous complaints about priests molesting children across western Victoria in the 1970s, '80s and '90s.

He kept the complaints secret and moved offenders to other parishes where a number continued to offend, the commission was told.

In Monday's hearing, Father McKinnon said he was not aware of the paedophilia problem until the late 1980s and did not question decisions made by Bishop Mulkearns.

He said the need to remain celibate led to a level of immaturity within the priesthood, which meant priests advising the bishop were not sensitive to the possibility child abuse was the reason some colleagues were being moved.